Tooth cleaning element



y 171, 1939- I c. H. SEIFERT 2,165,420

TOOTH CLEANING ELEMENT Filed July 29, 1957 Fig; 6.

Fig.1.

Patented July 11, 1939 1 UN ED s m'rrzs PATENT OFFICE 1f TOOTH CLEANINGELEMENT Charles Henry Seifert, Hempstead, N. Y.

Application July 29, 1937, Serial No. 156,413

1 Claim.

The invention aims to provide a new and improved tooth-cleaning elementconsisting of a sponge rubber block having a brushing surface at whichsome of the webs and cells of the sponge 5 rubber are exposed, having atleast one groove which opens through said brushing surface, and havingadentifrice filling each groove for direct application to the teethwhile the latter are being brushed with said brushing surface. A furtherobject'is to provide a cleaning ele ment of the class set forth in whichsome of the cells and webs of the sponge rubber are exposed at the wallsof the dentifrice-holding groove 01'- grooves, whereby the dentifriceand the-rubber may readily key together, obviating danger of thedentifrice falling from the groove or grooves before or during use.

A still further object is to provide a toothcleaning element welladapted for use as a refill for a toothbrush having means for removablyholding the same, one example of such a brush being shown in my UnitedStates application Serial No. 153,265, filed July 12, 1937, and anotherin my United States application Serial No.

a, 153,266, filed on the same date.

With the foregoing in view, the invention resides in the novel subjectmatter hereinafter described and "claimed, description beingaccomplished by reference to the accompanying drawing,

Figs. 1 to 8 inclusive are perspective views showing differentarrangements of dentifrice filled grooves in the rubber block.

Fig. 9 is an end elevation of Fig. 8.

Fig. 10 is a view similar to Fig. 9 but showing a slight variation.

Fig. 11 is an exaggerated detail sectional view showing the manner inwhich the dentifrice and the sponge rubber are keyed. together orinterlocked.

Various examples have been shown in the drawing, each consisting of asponge rubber block l2 having a brushing surface 13 (or a plurality ofsuch surfaces), one or more grooves I4 opening through said surface orsurfaces, and

a dentifrice I5 filling each groove. The grooves may be located andrelated with each other in a wide variety of ways as will be clear fromthe drawing and they may have right angularly related walls as shown forinstance in Fig. 5, curved Walls as shown in Fig. 9, acute angularlyrelated walls'as illustrated in Fig. 10, or they may be of any otherdesired cross-sectional shape.

Some of the webs'lS and cells ll of the sponge rubber are exposed at thebrushing surface l3 and others of said webs and cells are exposed at thewalls of the grooves l4, and by the latter exposure, the dentifrice l5and the sponge rubber may readily key together or interlock, obviatingdanger of the dentifrice falling out either 5 prior to or during use.While this dentifrice might well be in the form of an unusually thickpaste, it is preferably composed of appropriate tooth powder mixed witha water soluble binder, the grooves being filled with the mixture while10 the latter is plastic and being then partially dried with air andheat, the article however, being packaged in a moisture-proof containerbefore the mixture becomes hard and brittle, the nature of the containerinsuring that the dentifrice shall 15 not become excessively desiccatedwith danger of cracking and falling at least partially from the grooves.

When the cells and webs of the sponge rubber are exposed at the groovewalls to allow effective 20 interlocking between them and thedentifrice, it matters little what the cross-sectional shape of thegrooves may be, as long as it be such as to retain the dentifrice.However, it may be advantageous in some instances, particularly if 25the cells and webs be not exposed at the groove walls, to providegrooves of such cross-sectional shape that they are narrower at theiropen sides as illustrated for example in Figs. 9 and 10. If grooves ofthis nature are to be cut into the 30 sponge rubber block instead ofotherwise form-, ing them therein, it is of advantage to squeeze theblock sides adjacent the brushing surfaces together along their centralportions, imparting convex formations to the brushing surfaces by 35such squeezing and thereby facilitating the groove cutting. If thegrooves be cut with substantially parallel side walls while the brushingsurfaces are in convex form, said walls will move into outwardlyconverging relation when the 40 pressure on the block is relieved andsaid brushing surfaces return to fiat form. Grooves of the characterunder consideration may also be advantageously formed by cutting them inthe sponge rubber while the latter is still in sheets, and While bentover forms to stretch the surface to be grooved.

While the improved cleaning element could of course be used simply byholding it between 50 thumb and finger, it is preferably held in somesuitable form of holder for convenience. The device is of coursemoistened with water before use and the combined action of the wetdentifrice and the sponge rubber serve to effectively 55 clean theteeth. Then too, the sponge rubber provides an excellent means formassaging the gums. The dentifrice is, of course, yieldably backed bythe sponge rubber and works gradually from the grooves, effectivelyperforming its function Without danger of any excessive abrasive orsimilar action upon the teeth. The dentifrice-filled grooves preferablycover quite an extended area of each brushing surface and the device istherefore equally effective whether it be moved horizontally, verticallyor in a rotary manner.

While I have referred to l3 as the brushing surface, the real brushingsurface is formed jointly by the exposed side of the dentifrice insertand the surface l3, the relative areas being such that each forms aportion of the brushing surface.

I claim:

A tooth-cleaning element to be used once and thrown away, said elementcomprising an elongated substantially rectangular sponge rubber blockhaving a groove in one side, and a dentifrice insert filling saidgroove, one side of said dentifrice insert being exposed at said oneside of said block, the relative areas of said side of said block andsaid exposed side of said dentifrice insert being such that a brushingsurface is provided formed partly by said side of said block and partlyby said side of said dentifrice insert, the cells and webs of said blockbeing exposed at all portions of said brushing surface formed by theaforesaid side of said block, said groove being cross-sectionally shapedto retain said dentifrice insert therein, some of the cells and webs ofthe sponge rubber block being exposed at the walls of said groove toallow effective locking of the insert to the block.

CHARLES HENRY SEIFERT.

